The 1984 American presidential primaries have had their expectable result. The Democrats will go into the autumn elections under the leadership of a man selected by the basic constituencies of the party. And so will the Republicans.
This is the normal thing in American politics. It is the way it functions except in those years when a person comes along who can so impress his personality and his vision on the general public that, in effect, he forces himself upon a party.
This is not to be one of those elections in which the man is bigger than the party.
Walter Mondale went into the primaries as the preferred candidate of the labor unions and of those other special-interest groups that have provided the faithful party workers and the initial campaign funds for the Democrats since Franklin Delano Roosevelt put the combination together in 1932.
Walter Mondale emerges from the primaries as he entered them. He has won a majority of the delegates to the Democratic convention through the work of the organizations that backed him in the beginning. Politically speaking, he is the heir of Lyndon Johnson and of Hubert Humphrey, not of Jimmy Carter, who did in fact impose himself on a reluctant party.
Ronald Reagan won the 1980 election as the candidate of big business and industry (in rebellion against government regulation and against the power of the labor unions) and of the people in the higher income-tax brackets (who wanted relief from the steady climb in those taxes). They put up the funds that nominated Mr. Reagan four years ago and have provided his solid backing ever since.
If the nominations were decided by the independent voters who control the final outcome on election day, neither Mr. Mondale nor Mr. Reagan would be the candidates this year.
Among Democrats the young voters not yet integrated into the political system clearly preferred Gary Hart to Mr. Mondale. They responded to his promise to provide new ideas and a new approach to America's problems. But there were not enough of them to buck the machinery of the party.
Among Republicans, Mr. Reagan's renomination was demanded by his own special constituents. That demand was decisively reinforced by the prosperous state of the economy. The fact that inflation has declined and employment is improving, after the recession, ruled out any other choice.
But if independent voters had had a choice in selecting the Republican nomination, they would probably have preferred someone from a remarkably talented crop of younger Republicans typified by Howard Baker of Tennessee and Robert Dole and Nancy Kassebaum, both of Kansas.
Dwight David Eisenhower was the classic case of the man who imposed his own selection upon a party. He was offered the Democratic nomination by Harry Truman. He chose to seek the Republican nomination, and won it against the party machine, which much preferred Robert Taft of Ohio.
The effect of the Eisenhower election in 1952 was to give the country a President who was only mildly partisan. He owed his high office to a majority of the citizenry from all sections and classes. He could become, and indeed did become, a President of national reconciliation.
The 1984 American election would be a different story had Gary Hart been leading the Democrats and a Baker, Dole, or Mrs. Kassebaum leading the Republicans. The election of any one of those four would have been a leadership synthesizing the most durable features of the old ''New Deal'' with the more important changes wrought by Ronald Reagan.
Perhaps it is unfair to assume, as I do, that both Mr. Mondale and Mr. Reagan are too partisan to become synthesizers. One or the other may surprise me. But from the existing record, one can most logically assume that the real issue in the campaign will be whether the country prefers another four years of the Reagan counterrevolution - which means primarily the curbing of the rise in taxes and welfare and the curbing of the power of the labor unions.